Iron-containing thin films are mainly used as members of electronic components such as high dielectric capacitors, ferroelectric capacitors, gate insulators, and barrier films and magnetic bodies.
Methods for producing the above-mentioned thin films include flame deposition, sputtering, ion-plating, MOD processes such as coating thermal decomposition, sol-gel process and the like, chemical vapor deposition (hereinafter, may be simply described as CVD), and others. The optimum production process is chemical vapor deposition including ALD (Atomic Layer Deposition) because it has a number of advantages such as excellent performances in composition control and step-coverage, suitability for mass production, and capability of hybrid integration.
In MOD and CVD processes, compounds using organic ligands are used as precursors supplying metal to thin films. As the organic ligand, there has been reported an alcohol having an ether group or a dialkylamino group at the terminal, which provides a precursor with relatively high vapor pressure and hence is suitable for forming thin films by CVD. As for silicon, Patent Document 1 reports a silicon alkoxide containing a ligand derived from an alcohol having a terminal alkoxy group. There have been also reported various metal compounds containing ligands derived from alcohols having a terminal amino group, which is a donor group coordinating to a metal atom. Patent Document 2 and Patent Document 3 report titanium compounds and zirconium compounds, Non-patent Document 1 reports lanthanide compounds, and Non-patent Document 2 reports copper aminoalkoxide compounds.
As for iron, however, there is no report on an alkoxide compound having a terminal amino group or no report on evaluation of the method for forming thin films using such a compound.
Patent Document 1: Japanese Patent Laid-Open Publication No. H6-321824
Patent Document 2: Japanese Patent Laid-Open Publication No. 2000-351784
Patent Document 3: Japanese Patent Laid-Open Publication No. 2003-119171
Non-Patent Document 1: Inorganic Chemistry, Vol. 36, No. 16, 1997, p. 3545-3552
Non-Patent Document 2: Inorganic Chemistry, Vol. 36, No. 14, 1997, p. 2930-2937